By Rebecca Lewis @RebeccaSLewis
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Videographer / Director: International Animal Rescue
Producer: Nick Johnson
Editor: Sonia Estal
Just two months ago the orphaned animal struggled to sit up on his own, but now he can walk and even climb like a healthy ape.
One-year-old Budi was severely malnourished when he arrived at the International Animal Rescue (IAR) sanctuary in West Borneo, Indonesia, in December after a life spent caged in a chicken coop.
He was handed to the Sussex-based charity by his owner, who fed him nothing but condensed milk - believing the liquid would be enough sustenance for the baby ape.
But the lack of solid food left his bones in a brittle condition.
The slightest movement caused him so much excruciating pain he cried like a baby every time doctors touched him.
His body was swollen with fluid due to a lack of protein and he was suffering from severe anaemia.
After a lifetime of malnutrition his limbs were deformed and he was unable to use his arms and legs.
But after two months of dedicated care, Budi is eating fruit, walking and even climbing.
Alan Knight, OBE, IAR Chief Executive, said: “When you watch the latest video it’s hard to believe this healthy young infant is the same poor creature we found lying on his back in a cage, completely unable to move or sit up.
“When Budi was rescued he was so weak and fragile that we all feared he wouldn’t survive.
“But he has proved to be a real fighter and is now safely on the road to recovery.
“He still has a long way to go but his pain has subsided, the swelling in his body and limbs has disappeared, he has a healthy appetite and is becoming more energetic and active by the day.”
New footage captures young Budi swinging his legs and climbing a small structure with the help of veterinarian Dr Ayu Handayani.
But the intense exercise leaves him exhausted - forcing young Budi to take regular naps.
Staff at the centre are working round-the-clock to nurse Budi back to health.
It will take at least six or seven years of rehabilitation before the ape’s return to the wild can be considered.
Vet Karmele L Sanchez, IAR’s programme director in Indonesia, said: "At the moment we are still worried for Budi’s life and trying to minimise his pain.
“But he is a very determined little baby and is fighting hard to survive. The weeks and months ahead will be critical to his future and our veterinary team is doing all they can to help him pull through.”
Donate to help young Budi at http://www.internationalanimalrescue.org/budi